It doesn't matter that they contradict themselves. People see a report like this, with the word Cannabis along side words such schizophrenia, depression, paranoia, etc, and they'll automatically link the two. Even if they forget about this article by next week and somebody asks them about Cannabis they'll straight away think of schizophrenia, depression and paranoia. Then if the government asked the people to vote, or what they think about Cannabis, all these words that they now associate with Cannabis for no reason other than seeing them together will pop into their mind and they'll vote against Cannabis. That's how it works. They don't give a shit that they're contradicting themselves.